Plant Nature Study II by Jacob Joshua Levison Plant Nature Study II by Jacob Joshua Levison    

Lesson 17: Requirements of Trees: Light

Directions

Study the lesson for one week.

Over the week:

• Read the lesson.
• Review the synopsis.
• Recite aloud the vocabulary words and their definitions.
• Learn the concepts.
• Complete the enrichment activities.
• Study the review questions.

Synopsis

This lesson addresses light as a requirement of trees. Light enables assimilation, or plants taking in nutrients from their surroundings and turning them into plant tissue. Plants in general cannot grow without light. Without light they cannot make chlorophyll, they will lose their green color, and they will eventually die. Some plants grow well in shady locations and others require sunny locations. Trees growing in the open grow broad branches, while trees in the forest grow tall and lanky. In thick forests, where light cannot reach the bottom branches of trees, those bottom branches fall off in a process called natural pruning.

Vocabulary

Assimilation: The metabolic conversion of nutrients into tissue, including both photosynthesis and nitrogen fixation.
Natural Pruning: The death and natural dropping off of tree branches due to limited sunlight.
Forestry: The science of planting and growing trees in forests.

Concepts

TREE LIGHT AND FORM

Trees growing in the open tend to grow a broad crown of branches.

Trees growing in a dense forest tend to grow tall and lanky.

Trees growing in dense forests often undergo natural pruning.

Enrichment

Activity 1: Narrate the Lesson

• After reading or listening to the lesson, narrate the lesson aloud using your own words.

Activity 2: Study the Lesson Pictures

• Study the lesson pictures and describe how they relate to the lesson.

Activity 3: Take a Nature Walk

• Bring a small sketchbook and embark on a nature walk.
• Seek out and sketch four trees growing in different light conditions - a lone tree in an open field, a tree in a densely forested area, etc.
• Observe the form of the tree and the amount of light each receives.
• Use the gathered information to create the field book entry.

Activity 4: Complete a Field Book Entry   

After your nature walk, complete page 33 in 'Science Field Book for Fourth Grade.'

Review

Question 1

Describe a common form of a single tree growing in a well-lit open field.

1 / 5

Answer 1

Trees growing in the open tend to grow a broad crown of branches.

1 / 5

Question 2

You walk through a densely populated forest. Are you more likely to see trees with broad crowns or tall, lanky trees?

2 / 5

Answer 2

Trees growing in a dense forest tend to grow tall and lanky.

2 / 5

Question 3

Are you more likely to see examples of natural pruning in an open field populated by few trees or a dense forest?

3 / 5

Answer 3

You are more likely to see examples of natural pruning in a dense forest.

3 / 5

Question 4

What generally happens to plants if they have no light?

4 / 5

Answer 4

If plants have no light, they lose their chlorophyll, their green color fades, and they die.

4 / 5

Question 5

How does the amount of light affect the form of the tree?

5 / 5

Answer 5

Trees with lots of light grow broad crowns of branches while tightly packed trees lose their bottom branches due to natural pruning, growing tall and spindly to reach the light.

5 / 5

❮ ❯

1. Describe a common form of a single tree growing in a well-lit open field. Trees growing in the open tend to grow a broad crown of branches.
2. You walk through a densely populated forest. Are you more likely to see trees with broad crowns or tall, lanky trees? Trees growing in a dense forest tend to grow tall and lanky.
3. Are you more likely to see examples of natural pruning in an open field populated by few trees or a dense forest? You are more likely to see examples of natural pruning in a dense forest.
4. What generally happens to plants if they have no light? If plants have no light, they lose their chlorophyll, their green color fades, and they die.
5. How does the amount of light affect the form of the tree? Trees with lots of light grow broad crowns of branches while tightly packed trees lose their bottom branches due to natural pruning, growing tall and spindly to reach the light.

References

'Studies of Trees' by Jacob Joshua Levison. gutenberg.org/ebooks/16116. n.p.

'Assimilation (biology).' Wikipedia. Wikipedia.org. n.p.